Thomas Octavius Prichard (1808–1847) was an English psychiatrist, one of the earliest advocates of "moral management", the humane treatment of the mentally ill. Having served as superintendent for two years at Glasgow Royal Lunatic Asylum, Prichard was appointed founding superintendent of the Northamptonshire County General Lunatic Asylum in 1838.

[1] Funded by public subscription, it was intended for "private and pauper lunatics".

He saw non-restraint as part of "a system of kind and preventative treatment, in which all excitement is as much as possible avoided, and no care omitted": it is not clear whether he was influenced by the earlier work of Robert Gardiner Hill.

When the poet John Clare entered the asylum in 1841, Prichard encouraged him to continue his writing.

Prichard resigned from the Northampton asylum in 1845 following allegations of professional misconduct.